Filter-press cloth



July 8 HALE FILTER PRESS CLOTH Filed July 26 e Patented July 8, 1924.

y UNHTEE YATES HARRY c. HALE,

eena era QEFFEQEE,

OF BALTIMORE, MARYLAND, ASSIGNOR- TO WILLIAM E. I-IOOPER AND SONSCOMPANY, A CORPORATION OF MARYLAND.

FILTER-PRESS CLOTH.

Application filed July 26,

To all whom it may concern:

Be it known that I, HARRY C. HALE, a citizen of-the United States ofAmerica, residing in the city of Baltimore, State of Maryland, haveinvented certain new and useful Improvements in Filter-Press Cloths,

of which the following is a specification.

In the manufacture of cotton seed oil and in other similar processeswhere a liquid is obtained by filter pressing a finely divided solid orsemi-solid material as ground cotton seed or fruit, the material beingpressed is wrapped in a cloth called a press cake clot-h which holds thesolid material permitting the liquid to escape by filtration through thecloth. The cloth, in order to hold the solid material beingpressed, andto withstand the pressure sufficiently to prevent the es cape of thelatter, which would cause the solid to be mixed with the liquid, must beof a thickness corresponding to the pressure to be applied to it. Suchpressure ordinarily depends upon the nature of the material beingtreated. The present invention having been developed in connection withthe treatment of cotton seed in the production of cotton seed oil, thedisclosure relates particularly to the treatment of this commoditythough the invention is capable of 39 a more general application.

The fabric used in the wrapping of the.

filter cake, i. e., the filter cloth, must in the treatment of materialsrequiring high pres sure to extract the liquid therefrom as does theportions thereof which are subject to the direct pressure of filtrationparticularly where there is but a single thickness of the fabriccovering the filter cake. However, Q0

portions are not subject to the full pressure applied to the cake, anddo not perform the passed through them being also passed through atleast one other thickness. of the fabric.

filtering is extremely heavy, being composed of twenty or thirty ounceduck and. is proportionately expensive, and as it is used inconsiderable quantities, any saving which can be made in the weight ofthe fabric as .55 a whole, which means a corresponding save cotton seed,be correspondingly heavy as tov there are certain portions of thefabric, par-' full duty of filtration, the liquid which is 1923. SerialNo. 653,972.

ing in the fiber used and a proportionate saving in cost is of greatimportance.

In view of the necessity for economy in this connection, the inventorhas produced a filter press cake wrapper or cloth composed orconstructed of a fabric especially manufactured for this purpose, whichfabric is heavy and closely woven at the center, the weight and thecloseness of the weave being reduced as to the edge portions by reducingthe number of threads per inchover a margin of several inches, orwhatever seems desirable in view of the size of the filter cake, at eachside. In this way a considerable percentage of the weight and hence ofthe expense of the fabric is saved, and none of the utility thereofwhatever is sacrificed; the filter cloth being so constructed and foldedin operation that these edge portions are 1 always overlapped inwrapping the material so that they take neither the full stress incident to supporting the material during pressing nor the full pressureof the liquid in filtration meaning that a single thickness of thematerial is not subjected to the pressures referred to.

In the accompanying drawing I have illustrated a filter press clothembodying the features of my invention.

In the drawing:

Figure l is a plan showing the filter cloth open, viewing it from theupper side which comes next to the material in wrapping.

Figure 2 is a perspective view of a filter cake cloth, made inaccordance with invention.

Figure 3 is a plan of a fragment of the fabric of which the cloth of myinvention is made;

Figure l is a cross section of the wrapped filter cake taken on the line4-4t of Figure 2.

Figure 5 is a side elevation of the filter cake wrapped ready forpressing as shown in Figure 4.

Referring to the drawings by numerals,

the press cake cloth as shown in Figure 1 consists of a centrallongitudinally 'extend- The fabric which is used in high pressure itscentral portion 5,;extending the length of 'the material, ofconsiderably increased e h and, cl seness of tex e as compared to theedge portions, 6, the said thinner edge portions, 6, being in the clothillustrated some three or four inches wide. The differences in weightand texture referred to between the edges and the central portion of thestrip are preferably effected by varying the number of Warp threads tothe mob, it being understood that the warp extends from left to right ofthe press cloth as shown in Figure 1; said warp threads being indicatedby reference character, 7, and the weft by reference character, 8. Thearrangement of the weft is uniform throughout. The number of warpthreads per inch in the edge portions referred to being reduced tolighten the fabric and at the same time causing it to be of a loosertexture. Preferably the longitudinal edges, 9, of the fabric strip, 2,are uncut, the fabric being woven of the desired width.

The fabric strip, 2, woven with the thick, heavy closely woven centraledges, 6, is regarded as an important feature of my invention.

The side flaps, 3-4, may to advantage be likewise constructed of similarmaterial, i. e., a fabric strip having a central longitudinallyextending portion, 10, of increased weight and closeness of texture ascompared to the edge portions 11-12, it being understood that in neitherinstance is it important that the light edge portions be of uniformwidth. In fact the side flaps 3-4: are shown as woven with a narrow edgeportion, 12, of decreased weight and looser texture on one side, and awider edge portion, 11, of similar light looser texture on the otherside, the narrow edge portion, 12, being sewed to the center strip, 2,adjacent the central heavier portion, 5, thereof, and there being onesuch flap on each side, the longitudinal edges of the side flaps beinglaid parallel to the corresponding edges of the center strip, the warpthreads of all three memhers being parallel and it being understood thatthe variation in texture of the side flaps is produced in the samemanner, i. e., by varying the number of warp threads to the inch asdescribed in connection with the center strip.

The wrapped press cake, 14, is shown in Figures 2, 4 and 5. The wrappingof the press cake is accomplished by placing the material to be pressedon the center strip be tween the side flaps. The side flaps are thenfolded inward over it and the ends 15--16 .of the center strip arefolded over the side flaps, one being laid over the other as illustratedin Figures 2, 4c and 5, the package being then ready for pressing. Itwill be noted on examination of Figure 2 that the sides 17, of thepackage are upright and are covered by the heavier portion 10 of theside flaps, the lighter edge portions, 11, being folded over the top andthen covered by the ends, 1516 of the center strip, 2, and from furtherexamination of the drawing it will be noted that each side, 17, of thepackage is covered by at least one thickness of the heavy fabric, theoverlapping material being in the main of the lighter, looser texture,but it is not feasible in every instance to avoid entirely theoverlapping of the heavy portions of the fabric. The wrapper as arrangedavoids this to such an extent as to effect a very considerable saving inthe textile fiber used in the manufacture of the cloths without any losswhatever of efficiency, at the same time making the cloths lighter, moreflexible, and therefore, easier to handle.

It is possible and feasible to make filter press wrappers or cloths inaccordance with the principles of the invention for various otherpurposes than those referred to herein, as, for instance, cloths for usein pressing apples and other fruit in the manufacture ofcider, and insome instances it is found desirable to change the relative position ofthe thin and thickened portions of the cloth to conform to necessitiespresented, by the particular process in which cloths are used.

I have thus described specifically and in detail a single filter presscloth embodying my invention in order that the nature and operation ofthe same may be clearly understood. However, the specific terms hereinare used descriptively rather than in a limiting sense, the scope of theinvention being defined in the claim.

What I claim and desire to secure y Letters Patent is A filter presscake wrapper composed of i woven fabric consisting of a center strip ands1de flaps, the center strip having warp threads in the central portionthereof, closely laid, and Warp threads in the edge por tions thereofless closely laid producing a heavy closely woven central portion, and acomparatively lightloosely woven edge portion, the side flaps likewisehaving a heavy closely woven central portion and a lighter more looselywoven edge portion, the thickened portion of the centre strip serving tocover the top, bottom and ends of the press cake, and the thickenedportions of the side flaps serving to cover the sides of the press cake,the lighter edge portions serving to hold the flaps in positionsubstantially as described.

Signed by me at Baltimore, Maryland, this 20th day of July, 1923.

HARRY C. HALE.

' Witnesses:

HOWARD H. Toms,

LAWRENCE G. YEAGLE.

